TV Remote controlled home appliance circuit with 555 timer

This is my first post and and this is the first circuit i made. There are many types of circuits for controlling home appliances using TV Remote. In fact I had confused a lot when I am a beginner searching for this type of circuits. The circuit here 555 timer IC to avoid fast switching. you can only switch the circuit after 3 seconds.

IR remote sensor IC TSOP 1738 is used for recieving the signal. Normally when no signal is falling on IC3 the output of it will be high.This makes Q1 OFF.When a signal of 38 KHz from the TV remote falls on the IC3 its output goes low.This makes Q1 conduct and a negative pulse is obtained at pin 2 of IC 1 NE 555.Due to this IC1 wired as a monostable multivibrator produces a 4 Sec long high signal at its out put.

This high out put is the clock for IC 2 which is wired as a Flipflop and of , its two outputs pin 3 goes low and pin 2 goes high.The high output at pin 2 is amplified to drive the relay .For the next signal the outputs of IC2 toggles state. Result, we get a relay toggling on each press on the remote.Any appliance connected to this circuit can be switched ON or OFF.

The 555 timer is used to create a 3 sec delay for avoiding fast switching. You can also achieve this by using a high value capacitor across TSOP sensor. Click here to go view that circuit.

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